Ore flotation process and reagent



Patented June 17, 1930 UNETED STATES.

OFFICE The present invention relates to the froth flotation of minerals from ores, by the use of novel flotation ingredients, and is based upon our discovery that the reaction product of silicon sulfide with a group of substances, of which sodium alcoholate furnishes the typical example, produces a series of bodies having valuable flotation properties, when used in conjunction with a frothing agent, for the separation of minerals from ores.

The following reaction is typical of the reactionwhich apparently takes place, sodium ethylate being shown inthis reaction, but-it willbe understood that the methylate as well as its homologues and other substances as noted below, can be similarly employed.

SNa

siu-m compounds can be also employed. It is.

also found out that the alcohol itself can under some conditions be substituted for the ethylate, producing the corresponding acid,

in accordance with the following reaction.

' coin;

SiSH-HOCnH SSi The above substances namely thio-silicooxy-ethyl sodium sulfid and thio-silico-oxyethyl-th-io acid are to be regarded as typical of the alkyl compounds of the class mentioned. Of these compounds the ethyl derivatives have been found to be very satisfactory, and it is also found that the methyl compounds can be used. There appears to be no particular advantage in using the higher alkyl compounds such as propyl and butyl, which are more expensive than the ethyl compounds but they are also suitable.

The sodium salt above referred to can be prepared by suspending silicon sulfide in a solution of caustic soda in-strong alcohol, and

warming the mixture (say to 35 or 40 C.) until the reaction has been substantially con1 pleted. The reaction would go on, but more slowly, at room temperature. The sodium salt can be carefully decomposed with a rather weak organic acid, such as oxalic, or the calcium salt can be similarly treated.

In place of the sodium ethylate in the above example, sodium cresylate or phenate, sodium mercaptol, sodium cyclohexanol, mixed sodium salts of tar acids, also the cresol, phenol, tar acids, hydrogenated phenols (e. g. cycloheXanol) or mercaptol, or mixtures thereof, can be used. It will be understood that sodium compounds are here-' in referred to, but obviously the potassium, calcium, barium or strontium compounds can .be used, the group of metals hereinafter being referred to in the term alkali-forming metal. These compounds react 1n an analogous manner, the ring compounds requiring slightly higher temperatures, say up to 80 or 100 C.

It will be understood that when mercaptols are used, say sodium ethyl mercaptol, a compound soim SNa would be formed, and that when sodium cresylate is used a compound OCHgCaHg 4 s SNa would be formed, and that when the hydroxy compound, sayphenol is used, the compound I would be formed.

Thus it is seen that in the first formula given above the O can be replaced by S, and that the (1 H, can be replaced by another alkyl group or by an aryl group or an aralkyl group, and that the sodium can be replaced by hydrogen (as in the second formula salt I ss- SNa We may form the ester OCaHi ss' scam or withmethyl chlorid we may form a mixed ester OCIHI' S g v In place of the above mentioned com- -pounds, various other silicon-sulfur comred heat.

pounds may be used as flotation agents, notably silicon chlor-hydrosulfid, SiChSH or thefsalts or esters thereof. The hydrosulfid can be prepared in known manner by reacting on silicon chlorid with H S at about a The corresponding fluorin compounds also can be employed.

In the flotation of ores by the use of the above products, the said products are mixed with a frothing agent, such as pine oil or tar oil or distillates thereof, for example by mixing one part of the sodium salt with 2 to 5 parts of cresylic acid or with 4 to 6 parts of tar oil of a gravity of 1.03, and adding 1 to 3 parts of pine oil. A quantity of the said oily mixture is then thoroughly mixed with the ore pulp, for example in a tube mill or other device in which the ore pulp is being produced, and the amount of the said oily mix ture can vary between wide limits depending upon the nature of the ore under treatment.

For many casesabout 0.05 to 0.2 pounds of the siliconsulfur-containing reagent per ton of ore will be found satisfactory. The pulp is then subjected to the ordinary aeration flotation (or froth flotation) operation, producing a foam carrying the sulfide mineral from the The flotation can be conducted in a neutral, alkaline or acid circuit, as desired.

, 1. A process which comprises subjecting ores to froth flotation in the presence of a compound havingthe general structure sac in which D represents a diad metalloid element oxygen or sulfur, R represents an alkyl,

aralkyl.

2. A process for efiecting the froth -flota- 3. An ore-flotation agent, suitable for use in aerationflotation of minerals, which comprises a frothing agent and a thio compound of thio-silico oxy-alkyl.

4. A process for effecting the froth-flotation of minerals from ore materials which comprises subjecting the same in a liquid vehicle to froth-flotation in the presence of an alkali-forming metal thio compound of thiosilico oxy-alkyl. I

5. A process for efiecting the froth-flotation of minerals from ore materials which comprises subjecting the same in a liquid vehicle to froth-floation inthe presence of a frothing agent and'thio-sodium thio-silico oxyethyl.

6. A process for effecting thefroth-flotation ofv minerals from ore materials which comprises subjecting the same in a liquid vehicle to froth-flotation in the presence of a frothing agent and a compound containing the acid radical of a thio-silico oxy-alkyl thio acid.

7. An'ore flotation reagent containing a frother' and a member o-f'the series of compounds of the type formula in which D represents a diad element oxygen or sulfur, R represents alkyl, aryl or aralkyl I and M represents alkali-forming metal or hydrogen or alkyl or aral l or aryl, such compounds having good co lecting power when used in froth-flotation of ores.

' 8.'A process which comprises froth-flotation of ores in the presence of a silicon-sulfur compound.

9. A process which comprises froth-flotain aeration flotation of minerals, which comprises a frothing agent and a compound containing the acid radical of a thio-silico oxyalkyl thio acid.

' 12. An ore-flotation agent, suitable for use in aeration flotation of minerals, which comprises an oily material and a compound containing the acid radical of a thio-silico oxyalkyl thio acid.

In testimony whereof we have signed our names to this specification.

IRA H. DERBY. ORIN D. CUNNINGHAM.

tion of minerals from ore materials which comprises subjecting the same in a liquid vehicle to flotation in the presence of a frothing agent and a thio compound of thio-silico oxy-alkyl. 

